Indicating dial



E. G. DANIELsoN E1' AL INDICA'I'INQ'DIAL Fi'led Deo. 3, 1924 MGB@ muy ay [WHO TTMYIYJ.

Patented Sept. 1, 1925.

UNITED Vs'llxfrrzis :1P-Afr ERNEST G. DANIEILSON, F SAN FRANCISCO, AND'R-OGER M. WSIE, 10F OAKLAND.,

CALIFORNIA, ASSIGNGRS T0 E. T. 'CUNNINGII'AAMfOF JSANERANCISG0,Ci-lLiORNIA.

`rit-LoIca'rrne. .n1-Ari,

Application -led- December 3,1'924. SerialN'o. 753,649.

To all f'wwwt may concern.'

Be it known that we,vF1nNnsT G. DANIEL- soN and Roenn M. 'Vrsn, citizenso'fthe United States, and residents, respectively,

of the city and county of San Francisco, in

the State of California, and of the city of .Oaklanch in the countyof Alameda and State Yof* California, have invented a new and useful Indicating Dial, of which the following is a specification.

' rThis invention relates to a control dial, and more particularly to such as are used for varying an electrical characteristic of a circuit, such as radio circuits. Such dials areusually Vmade apart ofthe yknob or other manually operated element, by the aid of which the control is effected. For example Isuch dialsV may be attached to the shafts ofV condensers or variablek inductances or res1stances, and may cooperate with a tionary index to show the condition of the;

circuit that is controlled, orto indicate the waiielength or station to which 'the 'circuit is tuned. n lt is one lofthe objects of `our invention to improve in general the yconstruction vof such indicating dials.

It is another Object of our invention to make it possible to renew or replace the indicating portion ofthe device by providing a separable indicating dial.v

Our invention possesses other advantageous features, some of which with the foregoing, will be set forth at length in the following description, where we shall outline in full that form of the invention which we have selected for illustration in the drawings accompanying and forming part of the present specification.l Although in the drawings we have shown but one embodiment of the invention, we do not desire to be limited thereto, since the invention as defined in the claims may be embodied in other forms also.

Referring to the drawings:

Figure 1 isa plan View of an indicating dial embodying our invention; and

Fig. 2 is a section of the device illustrated in Fig. 1. y

ln the present instance, the dial is shown as supported on a shaft 11, whichmay be the shaft of a tuning element such Aas Aa variable condenser or a variable inductance. The dial comprises a thin circular support 12, preferably made of some metal such as aluminum, which may readily be stamped Vto the required'form.` Aprojectien 13 may v'be provided at one point of thisfsupportfin order to serve as a stop with Vrespect to some stationary clement on a surface 4con'- tiguous t0 the.bottomsu'rfac'e o'f the support 12', The "support 12 has a sliglitgc'en- Y tral'depression 141, as well as an aperture z'l5 therein, enten ding centrally thereof. u

The aperture 15serves to. accommodate an extension 16 of a stud 17. This stud'has a Vshoulder 18 which abuts Aagainst fthe Aedges of the aperture 15. VBeyond vthe lshoulder '18 'be upset over the outer 'edge of the aperture 15 so as to hold the stud 17 `firmly in :place the stud 17 has an extension 16 which Vmay is no interference from theexte'nding porl tion'of the studl 17 whenthe support 12 is placed near to a such `as the outer surface of ap'anel.

A set screw 19.passes radially of thestud andfis varrangedtofasten th'e'shaftp11 securely thereto.

Onv one surface ofthe supportV 12 :there is a dial 21, which may "be 'formed 'either 'in` tegrally or separably with respect to the support. In this inst-ance, we show the dial 21 as separable,and made of paper or of ,other light material. It has a central aperture large enough to pass over thepr0jecting central portion 22 of the support 12. This dial is marked in any appropriate manner, in the present instance being marked in 200 equal divisions, whereby the position of the shaft 11 with respect to a stationary index point may readily be determined by the aid of these markings. y In order to in-` cooperating v lia't (surface,

sure that the dial 21 will be properly positioned angularly with respect to the sup port 12, we provide a small circular projec tion 23, upset from the support 12, which fits intoa corresponding aperture in the dial 21. In this way it is cert-ain that the Zero'4 point of the dial 21 may always be made to fall immediately in line with the stop 13.

In order to clamp .the dial 21 detachably although securely in place, as well as to provide some manually controlling means for rotating 'the shaft 11, we provide a knob 24 which is preferably made of insulating material suchk as bakelite. a centralaperture 25 which is threaded to 'engage over the threads of the stud 17. TheV cated in Fig. 1, and is provided furthen more with the depending flange 26, forming an annular clamping surface 27 for the dial 21. This depending Wall 26 serves also to conceal the bushing 17 as Well as the set screiv 19, with the result that the entire dial structure presents a pleasing appearance. In order to strengthen the knob 24, several ribs or vanes 2S may be provided, connecting the flange 26 with the hub 29.

Vhen using the dial in connection with radiotuning apparatus such as variable condensers 0r inductances, it is advantageous to be able to inarlr on the dial the various stations or their call letters opposte the di vision point Where the electrical circuit Would be in tune to receive from the station. In the present instance a suteiently large space is provided for this purpose immediately inside of the ring 30 that carries the division mark.

The advantages of the construction as described are quite evident from the foregoing description. Comparatively few parts are necessary to construct the completed dial. It presents a neat appearance.y and provides sufficient room for marking the dial with various stations or their call letters. ln case itfbe required to replace or remove the dial 21, this may be done by removing the knob 9.11 from the stud 17 lVe claim:

1. In combination, a circular support, a dial disposed on one side of the support, a

stud clamped to the support, and a thumb nut having an annular clamping surface for cooperating with the dial, and threaded on Vsaid stud.

2. In combination, a circular dial having a depressed central portionin which there is an aperture, a member having an extremity with a shoulder abutting against the edge of the aperture in the dial, and With an eXtension passing through the aperture and upset so as to hold the member on the dial, the depression in the dial being sul'licient so that said extension does not extend beyond the depression, whereby the dial on the depression side may be held close to a flat surface, and a knob supported 0n the member. c 3. In' combination7 a circular support having a depressed central portion in which there is` an aperture, a. hollow stud having threads at one extremity, the other yextremity having a shoulder abutting against the edge of the aperture in the support, as Well as an extension passing through the aperture and upset so as to hold the stud on the support, the depression inthe support being suliicient so that said extension does not reach beyond the depression, whereby the support on the depression side may be held close to a fiat surface, a separable dial disposed on saidsupport lon the side opposite from the depression, and a knoby threaded on4 the stud havingV an annular clamping` surface for holding the dial to the support.

In testimony whereof We have hereuntoset our hands. 

